The present invention relates to a channel furnace for melting metals and alloys, and more particularly to a novel magnetic core for use in generating a three-dimensional magnetic field in such a furnace.
German Offenlegungsschrift No. 2,608,310 discloses a channel furnace having an inductor that generates both axially and radially oriented magnetic fields. The core of the inductor comprises a center core, which is designed as a solid round bolt having ends that are provided with threads for attachment of the core to support structure in the furnace, and an outside core, which is formed by substantially radial sheets, that are preferably in the shape of an involute. One disadvantage of this type of core lies in the fact that the solid bolt forming the center core characteristically is susceptible to high flux losses during the generation of alternating magnetic fields.